Common fault causes and troubleshooting methods of skeleton oil seals

The skeleton oil seal is a dynamic sealing element. The existence of “critical oil film” is a necessary and sufficient condition for oil seal sealing. Sealing without leakage is not allowed and impossible. Because the existence of the lubricating oil film is indispensable to ensure that the oil seal edge can realize the lubrication friction lock, and the existence of the lubricating oil film makes a certain amount of leakage inevitable. For rotary oil seal, it is allowed to have slight leakage within 50~100 hours during the initial operation. As the running time increases, the leakage will gradually stop, and the service life of such oil seals is often longer. Within the valid service life, trace leakage is allowed, otherwise, it must be handled according to the following common fault causes and troubleshooting methods of oil seal.
Poor framework oil seal, causing early leakage
No. Troubleshooting
1 Poor manufacturing quality of the lip of the framework oil seal, burr or defect on the edge of the framework oil seal, remove the burr or replace the framework oil seal
2 Poor quality or failure of framework oil seal spring Replace the framework oil seal spring
3 If the radial pressure is too small, the spring is too loose and the holding force is too small, adjust the spring of the framework oil seal
The framework oil seal is poorly assembled and leaks
No. Troubleshooting
1 When the lip of the framework oil seal has obvious scars, replace the framework oil seal by scratching the lip through the keyway or thread; When reinstalling, use a boot to protect the lip of the frame oil seal
2 The framework oil seal is butterfly shaped. The framework oil seal installation tool is improper. Redesign and manufacture the framework oil seal installation tool
3. The assembly direction of the lip of the framework oil seal is overturned or the spring is loose. The chamfer of the shaft end is improper, the roughness is too high, or the assembly force is too large, causing the lip of the framework oil seal to overturn or the spring to fall off. Use fine sandpaper to polish the chamfer of the shaft end, apply grease, and carefully install the framework oil seal
4 When too much grease is applied to the lip of the skeleton oil seal and the shaft surface, the grease will be reduced and returned to normal after the shaft has operated for a period of time